181 research outputs found

    Dyeing of cotton fabrics using reactive dyes by microwave irradiation technique

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    Dyeing of cotton fabrics with reactive dyes using exhaustion method has been done using microwave irradiation technique. Different parameters such as dye concentration, alkali concentration, salt concentration, power of microwave used and liquor ratio have been studied and the results are compared with conventional technique. It is observed that the microwave technique saves 90 min in the dyeing time 75% in the salt used and 20% in alkali used, indicating the saving in time, energy and money. The overall fastness properties to rubbing, washing, light and perspiration for the dyed samples are ranging from very good to excellent

    Relativistic Compact Objects in Isotropic Coordinates

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    We present a matrix method for obtaining new classes of exact solutions for Einstein's equations representing static perfect fluid spheres. By means of a matrix transformation, we reduce Einstein's equations to two independent Riccati type differential equations for which three classes of solutions are obtained. One class of the solutions corresponding to the linear barotropic type fluid with an equation of state p=γρp=\gamma \rho is discussed in detail.Comment: 9 pages, no figures, accepted for publication in Pramana-Journal of Physic

    A Novel Approach in Pigment Printing Using Nano-keratin Based Binder

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    This study is devoted to preparation and characterization of nano-keratin based binder (NKBB) from cheap renewable natural resources, namely coarse Egyptian wool or feather. The prepared NKBB is utilized as a biodegradable, environment-friendly and relatively cheap binder in textile pigment printing of polyester, pure polyacrylic, viscose, polyester/viscose, and polyester/acrylic fabrics. Different concentrations of the prepared NKBB as well as its mixture with commercially produced one are used in the pigment printing paste. The colour strength of the printed fabrics as well as their fastness properties to light, washing, and perspiration are evaluated. The effect of the used binder on the bending stiffness of the printed fabrics is also assessed. Results show that the NKBB gives almost the same colour strength and fastness properties as the commercial binder with improved stiffness of the printed samples in relation to that printed with commercial one

    On rigidly rotating perfect fluid cylinders

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    The gravitational field of a rigidly rotating perfect fluid cylinder with gamma- law equation of state is found analytically. The solution has two parameters and is physically realistic for gamma in the interval (1.41,2]. Closed timelike curves always appear at large distances.Comment: 10 pages, Revtex (galley

    Gyroscope precession in cylindrically symmetric spacetimes

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    We present calculations of gyroscope precession in spacetimes described by Levi-Civita and Lewis metrics, under different circumstances. By doing so we are able to establish a link between the parameters of the metrics and observable quantities, providing thereby a physical interpretation for those parameters, without specifying the source of the field.Comment: 13 pages, Latex. To appear in Class.Q.Gra

    Levi-Civita Solutions Coupled with Electromagnetic Fields

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    The local and global properties of the Levi-Civita (LC) solutions coupled with an electromagnetic field are studied and some limits to the vacuum LC solutions are given. By doing such limits, the physical and geometrical interpretations of the free parameters involved in the solutions are made clear. Sources for both the LC vacuum solutions and the LC solutions coupled with an electromagnetic field are studied, and in particular it is found that all the LC vacuum solutions with σ0\sigma \ge 0 can be produced by cylindrically symmetric thin shells that satisfy all the energy conditions, weak, dominant, and strong. When the electromagnetic field is present, the situation changes dramatically. In the case of a purely magnetic field, all the solutions with σ1/8\sigma \ge 1/\sqrt{8} or σ1/8\sigma \le - 1/\sqrt{8} can be produced by physically acceptable cylindrical thin shells, while in the case of a purely electric field, no such shells are found for any value of σ\sigma.Comment: Typed in Revtex, including two figure

    Static solutions of Einstein's equations with cylindrical symmetry

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    In analogy with the standard derivation of the Schwarzschild solution, we find all static, cylindrically symmetric solutions of the Einstein field equations for vacuum. These include not only the well known cone solution, which is locally flat, but others in which the metric coefficients are powers of the radial coordinate and the space-time is curved. These solutions appear in the literature, but in different forms, corresponding to different definitions of the radial coordinate. Because all the vacuum solutions are singular on the axis, we attempt to match them to "interior" solutions with nonvanishing energy density and pressure. In addition to the well known "cosmic string" solution joining on to the cone, we find some numerical solutions that join on to the other exterior solutions.Comment: 16 pages, 5 figures, 3 tables; many literature citations removed from main body; added historical section to put project into context and include additional reference

    Albumin Nano-Encapsulation of Piceatannol Enhances Its Anticancer Potential in Colon Cancer Via Downregulation of Nuclear p65 and HIF-1 alpha

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    Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC-BSA nanoparticles (NPs). These PIC-BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1α. Our results indicate that PIC-BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1α in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC-BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC-BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC-BSA NPs, enhances its therpautice potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possiable human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients
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